Inkjet printers can be used to print text, pictures, or other graphics by propelling droplets of liquid printing fluid onto a piece of printer paper or other media. Such printers will often include replaceable printer cartridges that house multiple printing fluid reservoirs which feed to corresponding cartridge printheads. The reservoirs will often contain different color printing fluids so as to allow the printer to print color graphics. For example, a printer cartridge can include a first reservoir that contains cyan printing fluid, a second reservoir that contains magenta printing fluid, a third reservoir that contains yellow printing fluid, and a fourth reservoir that contains black printing fluid.